Compound needle

ABSTRACT

A compound needle which includes a needle body  3  having a needle hook  15  at a front end thereof and a slider  5  having tongues  31   a,    31   b  formed by overlapping two blades  11   a  and  11   b  with each other and is so structured that the needle body  3  and the slider  5  are individually movable back and forth in the state in which the blades  11   a  and  11   b  of the slider  5  are supported in a blade groove  17  formed in the needle body  3,  wherein a partition wall  41  having thickness smaller than that of the needle hook  15  of the needle body  3  is formed in the blade groove  17  and the blades  11   a  and  11   b  of the slider  5  are accommodated in the blade groove  17  to sandwich the partition wall  41  therebetween, to thereby provide a reduced sliding resistance and a reduced degree of stretch of the blades when the blades are advanced beyond the needle hook.

TECHNICAL FIELD

The present invention relates to a knitting needle used in a knittingmachine. More particularly, the present invention relates to a compoundneedle comprising a needle body having a needle hook at its front endand a tongue constructed to be movable relative to the needle body andformed at the front end to cooperate with the needle hook so as to openand close the needle hook.

BACKGROUND ART

There is known a compound needle which comprises a needle body having aneedle hook at its front end and a slider and is constructed so that theneedle body and the slider can move relative to each other to open andclose the needle hook. The applicant previously proposed this type ofcompound needle in Japanese Patent No. 2946323.

The previously proposed compound needle is so constructed that twoblades of the slider are accommodated in an overlapped relation in ablade accommodation groove formed in the needle body. The blades areformed to have thickness smaller than width of the groove so as to forma gap between the blades and the groove walls so that the blades can besupported to freely advance and retract in the groove.

In the knitting machine using the compound needles as noted above, frontends of the two blades of the slider are brought into abutment withoutward inclined surfaces of the needle hook of the needle body at thefront end thereof, to be diverged right and left and then a knittingneedle on the opposite needle bed is moved into the space formed betweenthe two diverged blades advanced beyond the needle hook, wherebytransference of a loop is performed. The space formed between the twoblades varies depending on the widthwise dimension of the needle hookformed at the front end of the needle body. A rough gauge knittingmachine uses the compound needles each having a large needle hook and,with increase in size of a stitch formed, the size and thickness of theneedle hook increase. In the knitting machine disclosed by JapanesePatent No. 2946323 as previously cited, the two blades are placed on acenter line of the needle passing through the front end of the needlehook in the overlapped relation in the blade accommodation groove. Inthe case of a compound needle of rough gauge and large thickness, thispresents the disadvantage that when the blades are advanced beyond theneedle hook, the slider is abutted with the needle hook and is divergedright and left with increased sliding resistance, so that a burden isimposed on the slider and the needle hook. Further, when the blades aremoved to their advanced positions beyond the needle hook, the stretch ofthe blades increases to a large extent. This presents the problem for aknitting machine comprising a pair of front and back needle beds whichare arranged in opposition to each other and on which knitting members,such as a sinker and a loop presser, are disposed adjacent to thecompound needles, so as to be advanced and retracted with respect to aneedle bed gap. Specifically, in this knitting machine, there is thepossibility that when transference of a loop is performed, the bladesmay move closely to the knitting members to occupy the space forallowing the loop on the tongues to be transferred to a needle on thereceiving side, thus causing a knitting problem. Increase in spacingbetween the needle hook and the blade groove can allow the stretch ofthe blades to reduce to that extent, but this leads to elongation of theneedle body and the slider with respect to the lengthwise direction ofthe needle and further to increase in size of the carriage and theknitting machine itself.

It is the object of the present invention to disclose improvement of acompound needle of the type noted above, wherein the blades of theslider can be allowed to be advanced beyond the needle hook with areduced sliding resistance of the blades of the slider and a reduceddegree of stretch of the blades, as compared with the conventionalcompound needle.

DISCLOSURE OF THE INVENTION

The present invention provides a compound needle which comprises aneedle body having a needle hook at a front end thereof and a sliderhaving a tongue formed by two blades being combined in an overlappedrelation and is so structured that the needle body and the slider areindividually movable back and forth in the state in which the blades ofthe slider are supported in a blade groove formed in the needle body,wherein a partition wall having thickness smaller than that of theneedle hook of the needle body is formed in the blade groove and theblades of the slider are accommodated in the blade groove to sandwichthe partition wall therebetween. This construction of the compoundneedle of the invention can provide the result that when the slider isadvanced beyond the needle hook, the two blades, which are abutted withthe front end of the needle hook and diverged right and left by the sidesurfaces of the needle hook at the front end thereof, are made toadvance along lines deviating from a center line of the needle passingthrough the front end of the needle hook by the partition wall, so thatthe blades are stretched to a reduced extent in a widthwise direction ofthe needle, as compared with the conventional compound needle whereintwo blades are advanced along the center line of the needle passingthrough the front end of the needle hook.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view showing a forefront portion of a compound needle of thepresent invention which is in the state of being loaded in a needlegroove formed in a needle bed,

FIG. 2 is a view showing the detail of the respective parts of thecompound needle,

FIG. 3-a is a side view of the blades 11 a and 11 b;

FIG. 3-b is a plan view of the blades 11 a and 11 b; and

FIG. 3-c is a plan view of the blades 11 a and 11 b in the combinedstate,

FIG. 4-a is a sectional view of the forefront portion of the compoundneedle taken along line A—A of FIG. 1; and

FIG. 4-b is a sectional view of the same taken along line B—B of FIG. 1,

FIG. 5-a shows a slider which is in its retracted position;

FIG. 5-b shows blades of the slider which are in abutment with a needlehook;

FIG. 5-c shows the blades which are in their advanced position beyondthe needle hook; and

FIG. 5-d shows a conventional compound needle whose blades are in theiradvanced position beyond the needle hook, and

FIG. 6 shows a forefront portion of the compound needle of the presentinvention whose slider is in its retracted position.

BEST MODE FOR CARRYING OUT THE INVENTION

A certain preferred embodiment of the present invention will bedescribed below with reference to the accompanying drawings.

A compound needle of an embodiment of the invention comprises a needlebody 3 and a slider 5. The needle body 3 comprises a needle hook member7 and a needle jack 9 separate therefrom. While the needle body may beformed by these parts being integrally formed, the needle body 3 in theillustrated embodiment is formed by forming these individual parts incombination.

The needle hook member 7 is provided with a hook portion 15, a bladegroove 17 for accommodating a blade portion 11, a center body portion 19for supporting a lower arm of a slider body portion 13, and a concaveportion 21, provided at a rear end portion of the needle hook member,for connecting a front end of the jack, when cited in the order ofarrangement from the front end side. The needle hook member 7 and theneedle jack 9 are formed to have the same thickness. The needle jack 9is formed to have thickness slightly smaller than width of the needlegroove and has a curved elastic leg 23 extending rearwardly from theconcave portion 21 and having a rear end to abut with a bottom of theneedle groove. It also includes a control butt 25 projecting from aroundthe center of the body portion of the needle jack 9 to engage with a cammounted on a cam carriage (not shown), so as to be operated to advanceand retract, so as to make the needle body 3 advance and retract.

The needle hook member 7 has a partition wall 41 formed in the bladegroove 17 at a front end portion thereof. The partition wall 41 isformed to be placed on a dashed line X—X passing through the front endof the hook 15 and drawn in a lengthwise direction of the needle 1 asshown in FIG. 5-a and projected vertically upwardly from the bottom ofthe blade groove 17. The partition wall 41 is formed to be identical inheight to a throat portion 10 of the needle hook member 7 at a portionthereof on the front end side of the needle and be continuous to thebottom of the blade groove 17 at a portion thereof on the rear end sideof the needle. The blade groove 17 is divided into two groove portions17 a and 17 b by the partition wall 41, and the blades 11 a and 11 b areaccommodated in the groove portions 17 a and 17 b, respectively,sandwiching the partition wall 41 therebetween.

The slider 5 comprises blades 11 a and 11 b and a slider body 13 formedseparately from the blades. The blades are formed by two plates ofgenerally identical in shape to each other being combined in anoverlapped relation, as shown in FIG. 3, and are accommodated in theblade groove 17. The blades 11 a and 11 b have tongues 31 a and 31 b,formed at front end portions thereof, to abut with a front end portion15 a of the hook 15 and further have connecting portions 33 a and 33 b,formed at portions thereof on the rear side of the blade groove 17, toconnect with the slider body 13. Each of the blades 11 a and 11 b isbent outwardly at a location close to the connecting portion 33 a, 33 bso that when the blades are in the combined state, they can extendforwardly, keeping a space therebetween substantially equal to thicknessof the partition wall 41, as mentioned later. The blade 11 b has a bend35 formed therein. The bend 35 is put into abutment with inner sidewalls of the blade groove to prevent the slider 5 from moving awkwardlyin association with the advancing and retracting motion of the needlebody 3 and allow the needle body 3 and the slider 5 to advance andretract individually.

The slider body 13 has thickness identical to that of the needle body 3and has a control butt 49, projected from a rear end portion thereof,for controlling the advancing and retracting motion of the needle body.39 denotes a lower arm formed to be branched from the body portion andextended to a space in the center body portion 19 of the needle hookmember 7. The lower arm 39 has a longitudinal slot 51 formed by cuttingit at one side surface thereof and a thru hole 53 formed on thelongitudinal slot 51. The projections 33 a and 33 b of the blade 11 arefixedly engaged in the thru hole 53 of the slider body 13 by caulkingand the like.

Now, operation of the compound needle thus constructed will be describedwith reference to FIG. 5-a to FIG. 5-d. Shown in FIG. 5-d is aconventional compound needle which has no partition wall and is sostructured that two blades are combined in an overlapped relation witheach other at a widthwise center of the needle. For convenience ofexplanation, size of the needle hook and thickness of the blades aredepicted in an exaggerated form and also the slider body covering theblade groove from the above is omitted from FIG. 5.

When the slider is in its retracted position with respect to the needlebody 7, the blades 11 a and 11 b are respectively accommodated in theblade grooves 17 a and 17 b diverged right and left by the partitionwall. Then, when the slider 5 is advanced with respect to the needlebody 7, the blades 11 a and 11 b are abutted with the front end 15 a ofthe needle hook and then are stretched along the sides of the needlehook at the front end 15 a thereof, resulting in the state shown in FIG.5-c.

According to the conventional compound needle according to which twoblades 11 a and 11 b are combined in an overlapped relation and placedon a dashed line Y—Y passing through the front end of the needle hookand drawn in a lengthwise direction of the needle 1, when the blades 11a and 11 b are advanced beyond the needle hook, they come to bestretched outwardly to a large extent. Thus, the sliding resistance isincreased when the blades are advanced beyond the needle hook. Incontrast to this, according to the compound needle of the illustratedembodiment, the partition wall allows the two blades to be advancedalong lines deviating from a dashed line X—X passing through the frontend of the needle hook and drawn in a lengthwise direction of the needle1, and as such can allow the blades 11 a and the 11 b to be stretched toa small extent and can allow the sliding resistance to reduce. Inaddition, when the front ends of the blades 11 a and 11 b are extrudedalong the side surfaces 15 a of the needle hook at the front endthereof, the blades 11 a and 11 b are brought into contact with thepartition wall 41, which prevents portions of the blades 11 a and 11 baccommodated in the blade groove from being curved inwardly and, as aresult, the blades 11 a and 11 b are prevented from being stretched outto a large extent.

Also, when the blades 11 a and 11 b are moved to their retractedposition, as shown in FIG. 6, dirt and dust that may get into the spacebetween the blades ha and 11 b are pushed out by the partition wall 41.Hence, accumulation of the dirt and dust in the space between the blades11 a and 11 b can be avoided, thus avoiding the possible problemsresulting therefrom, such as hindrance of smooth sliding motion of theslider caused by the accumulated dirt and dust to cause unintendedknitting results, such as a drop stitch and a confined stitch (the statein which a stitch is confined within the hook of the needle), and damageof the slider and the needle hook. It is to be noted that with increasein thickness of the partition wall, the sliding resistance and thestretch of the blades can be made smaller. While in the illustratedembodiment, the space for the partition wall is formed between theblades 11 a and 11 b by bending the blades 11 a and 11 b, the space forthe partition wall may alternatively be formed therebetween by using aspacer to be inserted in between the two blades. The partition wall 41in the blade groove 17 may be formed along the entire length of theblade groove. Alternatively, the partition wall may be formed at anyother regions of the needle than the front end portion of the needle. Itis preferable, however, that the partition wall 41 is provided in afront region of the blade groove including a region on the front endside of the needle, because the partition wall formed at the front endportion of the blade groove 17 can prevent the accumulation of the dirtand dust in the space between the blades 11 a and 11 b.

Capabilities of Exploitation in Industry

As mentioned above, the compound needle of the present invention canprovide a reduced sliding resistance and a reduced degree of stretch ofthe blades when the blades are advanced beyond the needle hook, ascompared with the conventional compound needle wherein the two bladesare made to close contact with each other to be combined andaccommodated on the center line of the needle in the blade groove.

I claim:
 1. A compound needle which comprises a needle body having aneedle hook at a front end thereof and a slider having a tongue formedby two blades being combined in an overlapped relation and is sostructured that the needle body and the slider are individually movableback and forth in the state in which the blades of the slider aresupported in a blade groove formed in the needle body, wherein apartition wall having thickness smaller than that of the needle hook ofthe needle body is formed in the blade groove and the blades of theslider are accommodated in the blade groove to sandwich the partitionwall therebetween.